package main

import "fmt"

type cat struct{}

func main() {
	s0 := new([]int)
	fmt.Println(s0)
	s1 := []int{1, 2, 3}
	s2 := make([]int, 2)
	copy(s2, s1)
	s2[1] = 20
	fmt.Println(s1)
	fmt.Println(s2)
	s3 := []int{1, 2, 3}
	s4 := s3[:]
	s4[1] = 20
	fmt.Println(s3)
	fmt.Println(s4)

}
